bookstore.java

一个书店的例子

import java.sql.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.text.*;

public class BookStore{
	public static void main(String args[]){
		UI ui = new UI();
		ui.inital();	
	}	
}

class UI implements ActionListener{
	private Frame fm;		//主页面
	private Panel pm;		//管理页面
	private Vector books;	//图书信息
	private int[]  pq;		//购买数量 
	private int idx; 		//当前页码
	private Checkbox[] cb;	//标记购买框	
	private TextField[] tfpq;	//购买数量文本框
	private Button[]  bnote;	//内容介绍按钮组
	private Button	clear;	//全部清除按钮
	private Button	prev;	//转到上一页按钮
	private Button	next;	//转到下一页按钮
	private Button	jump;	//跳到指定页按钮
	private Button  review;	//浏览已选书清单按钮
	private Button	submit;	//提交按钮
	private Button 	ext;	//退出系统按钮
	private Dialog 	rew;	//统计对话框
	private Dialog 	dnote;	//图书内容介绍
	private TextArea revTa;	//已选书清单
	private TextField toPage = new TextField(4);	
	private String dbServer = "127.0.0.1";
	private Connection conn;
	private Statement stmt;
    private	NumberFormat nf1,nf2;
	
	
	public void inital(){
		this.connectDB();
		this.readDB();
		
		pm = new Panel();
		pm.setLayout(new GridLayout(16,1,1,1));
		pm.setBackground(new Color(95,145,145));
		this.connectDB();
		this.readDB();
		
		Panel p = new Panel();
		p.setBackground(new Color(95,145,145));
		p.setLayout(new FlowLayout(FlowLayout.CENTER,1,1));
		
		clear = new Button("全部清除");
		clear.setActionCommand("Clear");
		clear.addActionListener(this);
		
		prev = new Button("上一页");
		prev.setActionCommand("Prev");
		prev.addActionListener(this);
		
		next = new Button("下一页");
		next.setActionCommand("Next");
		next.addActionListener(this);
		
		jump = new Button("转到指定页");
		jump.setActionCommand("Goto");
		jump.addActionListener(this);

		review = new Button("已选书清单");
		review.setActionCommand("Review");
		review.addActionListener(this);
		
		submit = new Button("提交");		
		submit.setActionCommand("Submit");
		submit.addActionListener(this);
		
		ext = new Button("退出");
		ext.setActionCommand("Exit");
		ext.addActionListener(this);

		p.add(clear);
		p.add(prev);
		p.add(next);
		p.add(jump);
		p.add(toPage);
		p.add(review);
		p.add(submit);
		p.add(ext);
		
		nf1 = NumberFormat.getInstance();
		nf2 = NumberFormat.getInstance();
        nf1.setMinimumIntegerDigits(3);
        nf2.setMinimumFractionDigits(2);
		
		fm = new Frame("叮叮书店管理系统");
		fm.setLayout(new BorderLayout(1,1));		
		fm.add(pm,"Center");
		fm.add(p,"South");
		fm.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				System.exit(1);	
			}	
		});						
		fm.setSize(655,390);
		fm.setVisible(true);
		idx = 0;
		this.setButtonState();			
		this.showPage(idx);		
	}

	public void connectDB(){
		try{
		    Class.forName("oracle.jdbc.driver.OracleDriver");
		    String url = "jdbc:oracle:thin:@" + dbServer + ":1521:oradb";
		    conn = DriverManager.getConnection(url,"scott","tiger");
		    stmt = conn.createStatement();
		}catch(Exception e){
		    e.printStackTrace();
		}			
	}
	
	public void closeDB(){
		try{
			conn.close();
		}catch(SQLException e){
			e.printStackTrace();				
		}		
	}

	public void exit(){
		this.closeDB();
		System.exit(1);	
	}

	public void readDB(){
		books = new Vector();
		Book b;
		try{
		    ResultSet rs = stmt.executeQuery("select * from bstore");
			while(rs.next()){
				b = new Book(
					rs.getString(1).trim(),
					rs.getString(2).trim(),
					rs.getDouble(3),
					rs.getString(4).trim(),
					rs.getString(5).trim(),
					rs.getString(6).trim(),
					rs.getInt(7));
				books.add(b);				 
			}
			pq = new int[books.size()];
			cb = new Checkbox[books.size()];
			bnote = new Button[books.size()];
			tfpq = new TextField[books.size()];
			for(int i=0;i<books.size();i++){
				cb[i] = new Checkbox();
				bnote[i] = new Button("内容简介");
				bnote[i].setActionCommand("Note" + i);
				bnote[i].addActionListener(this);
				tfpq[i] = new TextField("",3);
			}			
		}catch(Exception e){
		    e.printStackTrace();
		}
	}
	public void updateDB(){
		Book b;
		String id;
		String sql; 
		try{
			for(int i=0;i<books.size();i++){
				if(cb[i].getState() && pq[i]>0){
					b = (Book)books.elementAt(i);
					id = b.getId();
					int q = b.getQuantity()-pq[i];
					sql = "update bstore set quantity =" + q +"where id='" + id + "'";
					stmt.executeUpdate(sql);
				}				
			}			
		}catch(Exception e){
		    e.printStackTrace();
		}			
	}

	public void showPage(int page){
		pm.removeAll();
		Panel p;
		TextField t;
    
        p = new Panel();
		p.setLayout(new FlowLayout(FlowLayout.LEFT,0,0));
		p.add(new Label("选购"));
		p.add(new Label("  编 号\t\t"));
		p.add(new Label("\t\t\t\t\t\t书      名\t\t\t\t\t\t"));
		p.add(new Label("\t\t\t\t\t出  版  社\t\t\t\t"));
		p.add(new Label("单价(元)"));
		p.add(new Label(" 购买数"));		
		pm.add(p);		
        		
        for(int i=page*15;i<(page+1)*15;i++){
			if(i>=books.size()) 	break;
			p = new Panel();
			p.setLayout(new FlowLayout(FlowLayout.LEFT,1,0));
			p.add(cb[i]);
			
			t = new TextField(nf1.format(i+1)+"",4);
			t.setEditable(false);			
			p.add(t);

			Book bk = (Book)books.elementAt(i);
			t = new TextField(bk.getName(),30);
			t.setEditable(false);
			p.add(t);

			t = new TextField(bk.getPublisher(),20);
			t.setEditable(false);
			p.add(t);
			
			t = new TextField(nf2.format(bk.getPrice())+"",4);
			t.setEditable(false);
			p.add(t);
			if(!cb[i].getState()){						
				tfpq[i].setText("");	
			}
			p.add(tfpq[i]);	
			p.add(bnote[i]);
			pm.add(p);					
		}
		fm.validate();		
	}
	
	public void actionPerformed(ActionEvent e){
		String s = e.getActionCommand();
		if(s.equals("Exit")){
			this.exit();	
		}else if(s.equals("Review")) {
			this.showSelectedBook();
			return;	
		}else if(s.equals("Submit")){
			this.purchase();
			return;
		}else if(s.startsWith("Note")){
			s = s.substring(4);
			int i = Integer.parseInt(s);
			this.showNote(i);
			return;	
		}
		
		if(s.equals("Next")){
			idx ++;
		}else if(s.equals("Prev")){
			idx --;
		}else if(s.equals("Clear")){
			this.reset();
		}else if(s.equals("Goto")){
			try{
				int i = Integer.parseInt(toPage.getText())-1;
				if(i>=0 && i<=books.size()/15)
					idx = i;	
			}catch(Exception e1){}
			toPage.setText("");	
		}

		this.showPage(idx);			
		this.setButtonState();			
	}

	public void reset(){
		for(int i=0;i<books.size();i++){
			pq[i] = 0;
			cb[i].setState(false);
		}		
	}
	
	public void createRevInfo(){
		Book b;
		revTa = new TextArea("",20,20);
		revTa.setEditable(false);
		revTa.setText("编号/书名/单价(元)/数量\n");
		revTa.append("----------------------------------------------------\n"); 
		double total = 0.0;
		for(int i=0;i<books.size();i++){
			try{
				pq[i] = Integer.parseInt(tfpq[i].getText());
			}catch(Exception e){
				pq[i] = 0;
			}
			if(cb[i].getState() && pq[i]>0){
				b = (Book)books.elementAt(i);
				revTa.append(nf1.format(i+1) + "\t" 
					+ b.getName() + "\t" 
					+ nf2.format(b.getPrice()) + "\t"
					+ pq[i] + "\n");
				total += pq[i] * b.getPrice(); 	
			}
		}
		revTa.append("----------------------------------------------------\n"); 
		revTa.append("应付总金额：" + nf2.format(total) + "元"); 
	}
	
	public void showSelectedBook(){
		if(rew!=null){
			rew.dispose();
		}
		Label title = new Label(" 您已选购了下列书籍：");
		title.setFont(new Font("Impact",Font.PLAIN,20));
		this.createRevInfo();
		rew = new Dialog(fm);		
		rew.add(title,"North");
		rew.add(revTa);		
		
		Button ok = new Button("OK");
		ok.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				rew.dispose();					
			}	
		});
		Panel p = new Panel();
		p.setLayout(new FlowLayout(FlowLayout.CENTER,1,1));
		p.add(ok);
		rew.add(p,"South");				
		rew.setSize(350,200);
		rew.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				rew.dispose();	
			}	
		});		
		rew.setVisible(true);			
	}

	public void purchase(){
		if(rew!=null){
			rew.dispose();
		}
		Label title = new Label(" 您的购书清单：");
		title.setFont(new Font("Impact",Font.PLAIN,20));
		this.createRevInfo();
		rew = new Dialog(fm,true);	
		rew.add(title,"North");
		rew.add(revTa);		
		
		Button ok = new Button("确认");
		ok.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				rew.dispose();
				updateDB();
				reset();
				showPage(idx);									
			}	
		});
		
		Button cancel = new Button("取消");
		cancel.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				rew.dispose();					
			}	
		});
				
		Panel p = new Panel();
		p.setLayout(new FlowLayout(FlowLayout.CENTER,1,1));
		p.add(ok);
		p.add(cancel);
		rew.add(p,"South");				
		rew.setSize(350,200);
		rew.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				rew.dispose();	
			}	
		});		
		rew.setVisible(true);
	}

	public void showNote(int bIndex){
		if(dnote!=null){
			dnote.dispose();
		}
		dnote = new Dialog(fm);
			
		Book b = (Book)books.elementAt(bIndex);
		Label title = new Label(" 图书内容介绍");
		title.setFont(new Font("Impact",Font.PLAIN,20));
		dnote.add(title,"North");
		
		TextArea noteTa = new TextArea("",20,20,1);
		noteTa.setEditable(false);
		noteTa.append( "编号：" + nf1.format(bIndex+1) 
					+ "\n书名：" + b.getName() + 
					"\n标准书号：" + b.getId() + 
					"\n作者：" + b.getAuthor() + 
					"\n单价：" + nf2.format(b.getPrice()) 
					+ "\n简介：\n    " + b.getNote() + "\n");
		dnote.add(noteTa);
		
		Button ok = new Button("OK");
		ok.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				dnote.dispose();					
			}	
		});
		Panel p = new Panel();
		p.setLayout(new FlowLayout(FlowLayout.CENTER,1,1));
		p.add(ok);
		dnote.add(p,"South");				
		dnote.setSize(300,200);
		dnote.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				dnote.dispose();	
			}	
		});		
		dnote.setVisible(true);			
	}

	public void setButtonState(){
		if(idx == 0){
			prev.setEnabled(false);	
		}else{
			prev.setEnabled(true);				
		}
		
		if(idx == books.size()/15){
			next.setEnabled(false);
		}else{
			next.setEnabled(true);	
		}			
	}

}

class Book{
	private String id;
	private String name;
	private double price;
	private String author;
	private String publisher;
	private String note;
	private int quantity;
	
	public Book(String id,String name,double price,String author,String publisher,String note,int quantity){
		this.id = id;
		this.name = name;	
		this.price = price;
		this.author = author;
		this.publisher = publisher;
		this.note = note;
		this.quantity = quantity;
	}

	public void setId(String id){
		this.id = id;
	}
	public void setName(String name){
		this.name = name;	
	}		
	public void setPrice(double price){	
		this.price = price;
	}		
	public void setAuthor(String author){	
		this.author = author;
	}		
	public void setPublisher(String publisher){	
		this.publisher = publisher;
	}		
	public void setNote(String note){	
		this.note = note;
	}
	public void setQuantity(int quantity){
		this.quantity = quantity;
	}
	public String getId(){
		return id;	
	}
	public String getName(){	
		return name;
	}		
	public double getPrice(){	
		return price;
	}		
	public String getAuthor(){
		return author;	
	}		
	public String getPublisher(){
		return publisher;	
	}		
	public String getNote(){
		return note;	
	}
	public int getQuantity(){
		return quantity;	
	}		
}